1. Technical Field
The present invention relates to a power supply device in which electrodes of multiple battery cells are connected to one another.
2. Related Art
Japanese Unexamined Patent Application Publication No. 2011-238544 discloses a related power supply device. The power supply device serving as a drive source of an electric motor is mounted on a hybrid vehicle or an electric vehicle, for example. A related power supply device of this type is illustrated in FIG. 1 to FIG. 5B.
As shown in FIG. 1 and FIG. 2, a power supply device 100 includes a battery cell assembly 101, and a battery connecting block 110 located on a side of the battery cell assembly 101 where electrodes protrude.
Multiple battery cells 102 are stacked in the same direction in the battery cell assembly 101. Each battery cell 102 includes a pair of electrodes (a positive electrode and a negative electrode) 103 protruding on an upper surface thereof. Each electrode 103 has a shape of a bolt.
The battery connecting block 110 includes a case body 111 made of an insulating resin, multiple connection terminals 121, a pair of output terminals 120, and multiple voltage detecting terminals 123 which are fixed to the case body 111, as well as two covers 140 configured to be fixed to the case body 111 and cover positions where the groups of terminals are placed.
The case body 111 includes a pair of terminal fixing areas S1 arranged in a longitudinal direction L on two end sides in a width direction W, and a wiring area S2 located outside the pair of terminal fixing areas S1 in such a manner as to surround the entire periphery of the pair of terminal fixing areas S1.
Multiple terminal fixing portions 112 and 113 are arranged in a row in each terminal fixing area S1. Every two adjacent terminal fixing portions 112 and 113 are connected to each other via a hinge portion 114 which is a flexural deformation portion. The pair of terminal fixing portions 112 placed on two opposite ends in one of the rows are provided for total power output. Each set of the output terminal 120 and voltage detecting terminal 123 is fixed to the corresponding terminal fixing portion 112 for total power output. The output terminal 120 and the voltage detecting terminal 123 are fastened to a corresponding one of the electrodes 103 located on two ends of the battery cell assembly 101 by using a nut 124. Each set of the connection terminal 121 and voltage detecting terminal 123 is fixed to the corresponding terminal fixing portion 113. The connection terminal 121 is fastened to the electrodes 103 of the adjacent battery cells 102 by using nuts 124, respectively. The voltage detecting terminal 123 is fastened together with the connection terminal 121.
Multiple wire housing portions 115 are continuously arranged in the wiring area S2. Every two adjacent wire housing portions 115 are connected to each other via a hinge portion 116 which is a flexural deformation portion. A voltage detecting wire (not shown) connected to each voltage detecting terminal 123 is routed in the corresponding wire housing portion 115.
The covers 140 are placed in each terminal fixing area S1, namely, placed above all sets of the terminal fixing portions 112 and 113 in the row, respectively.
As shown in FIG. 3 to FIG. 5B, each cover 140 includes multiple split cover portions 141 arranged in a row, and hinge portions 142 each being a flexural deformation portion configured to connect every two adjacent split cover portions 141 to each other.
Each split cover portion 141 and the corresponding set of terminal fixing portions 112 and 113 are provided with a set of a lock portion 150 and a position regulating portion 160 located at an interval in the longitudinal direction L.
Each lock portion 150 includes a lock arm portion 151 and a positioning hole 152 provided to the corresponding split cover portion 141, and a lock claw portion 153 and a positioning rib 154 provided to the corresponding terminal fixing portion 112 or 113. The lock claw portion 153 is locked with the lock arm portion 151. The positioning rib 154 on the terminal fixing portion 112 or 113 is inserted into the positioning hole 152 without any gap in the longitudinal direction L. The split cover portion 141 is positioned with respect to the terminal fixing portion 112 or 113 in the longitudinal direction L and is locked with the terminal fixing portion 112 or 113 by the lock portion 150.
Each position regulating portion 160 includes a position regulating hole 161 provided to the corresponding split cover portion 141, and a position regulating rib 162 provided to the corresponding terminal fixing portion 112 or 113. The position regulating rib 162 is inserted into the position regulating hole 161 with a gap (2×d) in the longitudinal direction L. The position regulating portion 160 enables the position regulating rib 162 to be inserted into the position regulating hole 161 even if there is a tolerance in assembling the battery cells 102 and the like, whereby the position in the width direction of the split cover portion 141 is regulated with respect to the terminal fixing portion 112 or 113.
In the above-described configuration, even when the dimension in the longitudinal direction L of the battery cell assembly 101 varies due to a tolerance in assembling the battery cells 102 and the like, the case body 111 absorbs the tolerance by flexural deformation of the hinge portions 114 between the terminal fixing portions 112 and 113 as well as the hinge portions 116 between the wire housing portions 115. Meanwhile, even when the dimension in the longitudinal direction L of the battery cell assembly 101 varies due to a tolerance in assembling the battery cells 102 and the like and relative positions of the terminal fixing portions 112 and 113 vary as a consequence, the covers 140 are attached to the case body 111 owing to tolerance absorption achieved by the position regulating holes 161 and the position regulating ribs 162 and tolerance absorption achieved by flexural deformation of the hinge portions 142.